Before he passed away, Sayyiduna Umar (radi Allahu anhu) appointed a six-man Committee to elect his successor from among themselves. After long discussions and consultation, they elected Sayyiduna 'Uthman bin Affan (radi Allahu anhu) as the third Caliph of Islam.
EARLY LIFE

Sayyiduna 'Uthman (radi Allahu anhu) belonged to the Ummayah tribe of the Quraish. He was a very rich cloth merchant. He was known as "Al Ghani" or "The Generous." His father's name was Affan and his mother was Urwa.
He accepted Islam at the invitation of Sayyiduna Abu Bakr (radi Allahu anhu) and migrated to Abyssinia with his wife, Sayyadah Ruqayyah (radi Allahu anha), who was also the daughter of Sayyiduna Rasulullah (sallal laahu alaihi wasallam).
After she passed away, he married Sayyadah Umme Kulthum (radi Allahu anha), another daughter of Sayyiduna Rasulullah (sallal laahu alaihi wasallam). Because of this, he earned the title "Zun Noorain" or "Possessor of Two Lights." He took part in all the battles with Sayyiduna Rasulullah (sallal laahu alaihi wasallam) except the Battle of Badr.
CONQUESTS

During the Khilaafat of Sayyiduna 'Uthman (radi Allahu anhu), the rebellion in Azerbhaijaan and Armenia was silenced.
Sayyiduna Mu'awiyah (radi Allahu anhu), with the help of Sayyiduna Abi Sarah (radi Allahu anhu), captured Cyprus by naval attack and brought it under Islamic rule. Vast areas of North Africa including Tripoli, Tunisia and Morocco were also brought under the Islamic rule.
The Romans, although defeated several times by the Muslims in the past, made another attempt, during the Khilaafat of Sayyiduna 'Uthman (radi Allahu anhu), to recapture the lands they had already lost. Constantine, the Emperor of Rome, made great preparations and attacked Alexandria with a naval fleet five to six thousand strong. But, the Romans were defeated by the Muslim naval forces under the command of Sayyiduna Abi Sarah and Sayyiduna Mu'awiyah (radi Allahu anhuma).
REBELLION

The Governors of the provinces, appointed by Sayyiduna Umar (radi Allahu anhu), were removed and replaced by members of the new Caliph's clan. The majority of the new governors were inspired by worldly means rather than by piety and interests of their subjects. People started to demand the removal of these Governors, but the Caliph did not respond to their appeals. Delegates mainly from Iraq and Egypt, submitted their demands to the Caliph. The situation, however got out of control.
ASSASSINATION

In the turmoil, Sayyiduna 'Uthman (radi Allahu anhu) himself was made Shaheed by rebels while he was reading the Holy Quran inside his house. This happened on Friday, the 17th of Zil Hajj in 35 A.H.. He was 84 years old.
CHARACTER

Sayyiduna 'Uthman (radi Allah anhu) was a very simple and very kind person. His simplicity and kindness did not alow him to take strong action against the trouble makers and rioters. Above all, because of his simple-mindedness, his administration was not as disciplined as it had been during the Khilaafat of Sayyiduna Umar (radi Allahu anhu).
Sayyiduna 'Uthman (radi Allahu anhu) was a generous man. He used to spend a lot of money for Islam and to free the slaves. He was a great and pious man who feared and loved Almighty Allah and Sayyiduna Rasulullah (sallal laahu alaihi wasallam) above everything else. Although he was very rich, his living was very simple. He did not indulge in luxury. He was ever mindful of death. Major parts of the night were spent in Salaah. He also fasted every second or third day.
THE HOLY QURAN

A major achievement of Sayyiduna 'Uthman (radi Allahu anhu) was the duplication of the Holy Quran from the records kept by Sayyiduna Abu Bakr (radi Allahu anhu), who handed it to Sayyiduna Umar (radi Allahu anhu), who then handed it to his daughter, Sayyadah Hafsa (radi Allahu anha), the wife of Sayyiduna Rasulullah (sallal laahu alaihi wasallam).
Sayyiduna 'Uthman (radi Allahu anhu) made copies of the Holy Quran from the original and sent it to capitals such as Kufa, Damascus, Makkatul Mukarramah and Basrah, each accompanied by a Sahabi for the guidance of the readers.